Bryce Harper out until early July with torn left thumb ligament

Bryce Harper will be sidelined for roughly eight to 10 weeks due to a torn thumb ligament. (Nick Wass/AP)

The Washington Nationals got their biggest and worst injury news of the season on Monday, when the team learned that outfielder Bryce Harper will likely miss the next two months after suffering a torn ulnar collateral ligament in his left thumb. The injury, which occurred on a slide into third base in Friday's game against San Diego, will require surgery, according to ESPN's Keith Law.

Harper was placed on the 15-day disabled list on Sunday, two days after injuring his hand on a head-first slide on a triple. The 21-year-old outfielder had already missed time this year with a strained quad muscle, and lost 44 games last season to a series of injuries, including a knee injury sustained in mid-May when he collided with the rightfield wall in Dodger Stadium trying to chase down a flyball.

Harper's absence will further stress a weakened Nationals lineup that is already without catcher Wilson Ramos and third baseman Ryan Zimmerman. Ramos suffered a fractured hamate bone on Opening Day against the Mets, and Zimmerman is sidelined with a fractured thumb suffered diving back into the second base bag on April 12 against Atlanta. To replace Harper in leftfield, the Nationals will likely use a platoon of Nate McLouth and Kevin Frandsen, each of whom started once in the two games Harper has missed since injuring his hand. The team could also bring up 25-year-old outfield prospect Steven Souza, who spent five games with the team earlier in the season.

Harper was hitting .289/.352/.422 with one home run, nine RBI and a stolen base for the Nationals this season.